Vacuum bag sealing machine



July 29, 1958 R. s.' RANDALL. 2,844,925 VACUUM BAG sEALING MACHINE:

Fiied July 11. 1955 INVENTOR. /7

I ffwww 14 TTORNE Y 'United tates Patent VACUUM BAG SEALING MACHINE Application July 11, 1955, Serial No. 521,176

' 6 claims. (ci. ssl-s6) The present invention relates to improvements in a vacuum bag sealing machine, and has particular Vreference to a machine of the type described in my copending application, Serial Number 486,797, filed February 8, 1955.

In the latter application it was proposed to provide a machine comprising in its general features a platform adapted to receive a number of open-ended bags thereon in side-by-side relation, a cover hinged to the platform and operable for lowering upon the same to form a housing therewith, means for evacuating the housing, heat sealing elements adapted for lowering on the open ends of the bags for sealing the same, and means for operating the heat sealing elements in timed relation tothe evacuating process.

When the bags are originally placed upon the platform, it becomes necessary to properly position the same with respect to the descending heat element, and it furthermore is desirable that the ends of the filled bags be flattened out prior to the application of `the sealing elements.

In the machine described in the pending application, I provided for this purpose a pair of co-operating'spring ngers which would advance slightly ahead of the sealing elements, and which would spread upon the end of the bag for flattening the same.

This arrangement, while working satisfactorily, gave no particular guide to the operator in placing the bags, and in the present invention, it is proposed to provide a bag-anchoring means, which allows the operator to denitely position each bag in its proper place, without variations in relative positions, and to anchor each bag in a swift sweeping movement.

It is further proposed to provide an anchoring means of the character described which acts on the eXtreme lend of the bag, leaving an immediately adjacent portion of the neck of the bag free for the sealing operation.

Another object of my invention is to arrange the anchoring means in such a manner as to leave the open end of the bag perfectly flat, while still providing a slight slit sufficient to allow the bag to be evacuated prior to the sealing operation.

And nally, it is proposed to provide an improved form of mechanism for operating the bag sealing means.

While l have shown only the preferred form of my invention, it should be understood that various changes or modifications may be made within the scope of the claims hereto attached, without departing from the spirit of the invention.-

The preferred form of my invention is illustrated in the accompanying drawing, forming part of this application, in which:

Figure 1 shows a fragmentary longitudinal section through one unit of my bag-sealing machine;

Figure 2, a transverse section through the same; l y

Figure 3, a plan view of the front portion of the platform, with the anchoring means attached thereto;

Figure 4, a detail plan view of a portionV of the plat- ICC form showing one bag in position with respect to its anchoring means;

Figure 5, a plan view of an anchoring strip used in my invention, a central portion being broken away;

Figure 6, a section taken along line 6-6 of Figure 3;

Figure 7, a section taken along line 7--7 of Figure 3; and

, Figure 8, a front view of the anchoring strip with attendant parts, a central portion being broken away.

Of particular interest for the purposes of the present invention is the platform 1 with its bag anchoring means shown at 2 in Figure 3.

The platform is preferably made rectangular in shape, with a forward edge 3, parallel side edges 4, and a straight rear edge running parallel to the front edge and spaced from the same sufficiently to allow a number of bags 5 to be arranged on the platform in spaced and parallel relation.

The bags are of conventional form, rectangular in shape, with simple folds at opposite sides thereof, and With open ends presented forwardly on the platform.

A plurality of heat-sealing elements 6 corresponding in number to the number of bags to be sealed, are mounted over the platform transversely, with freedom of vertical reciprocating motion over a section of the platform spaced from the front edge thereof, this section being occupied by the ribbon 7 of cork or similar material adapted to take the impact of the descending heating elements.

The bags, which have been previously lilled with sliced meats, sausages or the like, are placed on the platform, with their open ends overlying the cork ribbon and their front edges registering with the front edge of the ribbon.

y The principal object of the present invention is to provide the means, indicated at 2, for allowing the operator to quickly and expeditiously anchor the bags in their proper positions, while vleaving a slit allowing air to be exhausted from each bag.

For this purpose, I provide a number of strips 8 of metal or similar material, one for each bag. These strips are mounted on a strap 9, also made of metal, and secured upon the platform immediately forward of the ribbon, the strap being of the same thickness asV the ribbon, so as to present an upper face in co-planar relation with the upper face of the cork ribbon.

Each strip comprises a plain, at body portion of a width corresponding to that of the strap 9 and of a length somewhat less than the width of the bag to be used in connection therewith. The strips are secured upon the strap lengthwise,vin sufficiently spaced relation to conveniently allow for the eXtra widths of the bags and of a convenient spacing of the latter on the platform.

Each strip is provided, at its left end, with a short tongue 10 projecting over the cork ribbon 7 for a short distance. The tongue is intended to catch in the side fold of the bag, as the open end of the latter is guided over the ribbon in a short side sweep.

The tongue 10 has a straight side edge 11 alined with the corresponding edge of the strip, and its rear edge curves into its right edge, as shown at 12.

The top surface of the tongue lies in the top plane of the strip, but its bottom face 13 is slightly raised with respect to the top surface of the cork ribbon for accommodating the thickness of the bag material.

The bottom face of the tongue tapers upward from left to right and from front to rear, as shown at 14 and 1S, respectively, to clear the bag material as the latter is stretched against the left edge 11 of the tongue. Y

The short side sweep, which causes one fold of the bag to catch .behind the tongue 10, brings an-intermediate portion of the open end of the bag opposite a second tongue 16 projecting from the right end of the strip 8 over the cork ribbon, and this tongue is intended to allow the combined thicknesses of the bag material to be slipped thereunder and to be firmly'held thereby.

The second tongue 16 is constructed of soft rubber, or similar yielding, elastic material, and comprises a solid block of rubber 17 held adhesively in a pocket Y18 formed in the right end of the strip and an extension 19 projecting over the cork ribbon.

The extension 19 has a bottom face tapered at its rear portion, as at 20, and bearing flat on the cork ribbon in its forward portion, as at 21, so that the two thicknesses of the bag may be readily slipped underneath the tapered section and squeezed between the cork and the llat portion 21 of the tongue.

Thus, the operator, holding the bag slightly open, may readily position the same by anchoring one side fold of the bag against the left tongue and then slipping a distant portion of the combined thicknesses of the bag underneath the right tongue. This simple movement brings each bag into the exact position desired.

Since the left tongue catches inside one of the bag folds and the right tongue compresses both thicknesses, there will be a tapered slit between the two thicknesses of the bag material, just suicient to allow the bag to be evacuated when a vacuum is applied thereto.

The sealing element may be operated and the entire vacuum process sealing operation carried out in the manner described in the co-pending application, it being understood that a cover or super-structure 22 'is hingedly applied to the platform to form a vacuum chamber23 therewith when the cover is lowered upon the platform.

A certain improvement is provided in the operating means insofar as a diaphragm is substituted for the piston used in the co-pending application.

The operating means, as shown, comprises a head 23 for each sealing element mounted in the cover 22, which is suitably apertured, as at V24.

The head includes a lower cylindrical base 25 secured upon the cover by means of a flange 26 and bolts 27 and a cap 28, the base and the cap havingV cooperating flanges 29-30 clamped upon an interposed diaphragm 30A by means of bolts 31.

The diaphragm carries a central bolt 32, and is mounted upon the same by means of a lower washer 33, and upper washer 34 and a nut 3S threaded upon the upper end the washer.

The bolt extends downwardly through the base and a cross-member 36 at the bottom of the base, and is normally urged upward by a spring 37, the lower end of which bears on the cross-member, while its upward end exert upward pressure on the disc 33.

A nut 38 threaded on the bottom end of the bolt and bearing against the cross-member 36 is used for adjusting the position of the bolt.

The lower end of the bolt terminates in a fork 39 which has the sealing element 6 pivotedtherein, as at 40. The fork carries a cross-member 41 above the sealing element, with a pair of screws 42 arranged to limit the swinging movement of the said element.

The sealing element is in the form of a flat plate.43 mounted on edge, ,with a lateral groove 44 in which the heating element 45 is accommodated.

The upper end of the bolt is formed with a port 46 establishing communication between the spaces above and below the diaphragm. This port is normally closed by a conventional 'tire valve, but is opened when the valve stem, indicated at 47 is forced into contact with the upper wall of the cap 2B, that is whenever the sealing element is in raised or inactive position.A

A hole 4S in the side wallV of the cap communicates with a conduit 49A controlled by the solenoid valve 50, the conduit connecting with the atmosphere.

The operation of the above-described mechanism is similar to that described in my co-pending application.

When a vacuum is applied to the chamber 23, air is withdrawn, not only from the space below the diaphragm, but also from the space above the diaphragm and the tube 49, up to the solenoid valve 50.

Thus, the diaphragm remains unaffected during the beginning of the suction period.

When the vacuum reaches a desired degree, it opens, through any suitable means, the solenoid valve 50, and air is allowed to rush into the space above the diaphragm and urges the latter downward.

Upon initiation of the downward movement, the valve in the port 4.6 closes and the fully atmospheric pressure operates on the diaphragm to force the heat-sealing element upon the cork ribbon for heat-sealing the end of the bag.

I claim:

l. In a machine of the character described, a platform adapted to receive an open-ended bag thereon, and means mounted on the platform for anchoring the open end of the bag thereto, the said means comprising a strip of material anchored to the platform, a tongue projecting forward from one end of the strip and adapted for engagement in one side fold of the bag, and a second tongue projecting forward from the strip in spaced relation to the first tongue and adapted for clampingly receiving a distant portion of the bag end thereunder.

2. In a machine of the character described, a platform adapted to receive an open-ended bag thereon, and means mounted on the platform for anchoring the open end of the bag thereto, the said means comprising a strip of material anchored to the platform, a tongue projecting forward from one end of the strip and adapted for engagement in one side fold of the lbag, and a second tongue projecting forward from the strip in spaced relation to the first tongue and adapted for clampingly receiving a distant portion of the bag end thereunder, the rst tongue being spaced with respect to the bottom plane of the strip and having a straight end edge and being made to taper inwardly to a relatively sharp edge so as to clear the bag material.

3. In a machine of the character described, a platform adapted to receive an open-ended bag thereon and means mounted on the platform for anchoring'the-open end of the bag thereto, the said means comprising a strip of material anchored to the platform, a tongue projecting forward from one end of the strip and adapted for engagement in one side fold of the bag, and a second tongue projecting forward from the strip in spaced relation to the first tongue and adapted for clampingly receiving a distant portion of the bag end thereunder, the second tongue being made of resilient material and having a bottom face with a front portion disposed in the bottom plane of the strip and a rear portion tapering upwardly to facilitate introduction of the bag material under the front portion.

4. In a machine of the character described, a platform adapted to receive an open-ended bag thereon, and means mounted on the platform for anchoring the open end of the bag thereto, the said means comprising a strip of material anchored to the platform, a tongue projecting forward from one end of the strip, and adapted for engagement in one `side fold of the bag, ,and a second tongue projecting forward from the strip in spaced relation to the rst tongue and adapted for clampingly receiving a distantV portion of the Abag end thereunder, the first tongue being spaced with respect to the bottom plane of the strip and having a straight end edge and being made to taper inwardly to a relative sharp edge so as Vto clear the bag material, and the second tongue being made of resilient material and having a bottom face with a front portion disposed in the bottom plane of the strip and a rear portion tapering upwardly to facilitate introductionof the bagmaterial under the front portion,

6 5. In a machine of the character described, a platform open end overlying the ribbon, and means overlying the having a ribbon of soft material mounted transversely forward edge of the ribbon for anchoring the extreme thereon, the platform being adapted to receive an openend of the `bag thereto, and a heat-sealing element movended bag thereon rearwardly of the ribbon and with able over 'the ribbon rearwardly of the anchoring means the open end overlying the ribbon, and means overlying 5 and co-operable with the ribbon in sealing the bag, the the forward edge of the ribbon for anchoring the exheat-sealing element having a suction-responsive diatreme end of the `bag thereto, the anchoring means comphragm for operating the same, with means for delaying prising a pair of spaced tongues, one adapted for catchaction of the diaphragm until a desired degree of vacuum ing inside the bag for holding the latter against sidehas been obtained.

wise movement and the other for compressing opposing 10 sheets ofthe bag ata spaced point. References Cited in the file of this patent 6. In a machine of the lcharacter described, a platform UNTTED STATES PATENTS having a ribbon of soft material mounted transversely 2,672,268 Bower M a r. 16, 1954 thereon, the platform being adapted to receive an openended bag thereon rearwardly of the ribbon and with the 15 

